.\"     Title: \fBmysqlcheck\fR
.\"    Author: 
.\" Generator: DocBook XSL Stylesheets v1.70.1 <http://docbook.sf.net/>
.\"      Date: 11/02/2006
.\"    Manual: MySQL Database System
.\"    Source: MySQL 4.1
.\"
.TH "\fBMYSQLCHECK\fR" "1" "11/02/2006" "MySQL 4.1" "MySQL Database System"
.\" disable hyphenation
.nh
.\" disable justification (adjust text to left margin only)
.ad l
.SH "NAME"
mysqlcheck \- a table maintenance and repair program
.SH "SYNOPSIS"
.HP 46
\fBmysqlcheck [\fR\fB\fIoptions\fR\fR\fB] [\fR\fB\fIdb_name\fR\fR\fB [\fR\fB\fItbl_name\fR\fR\fB ...]]\fR
.SH "DESCRIPTION"
.PP
The
\fBmysqlcheck\fR
client checks, repairs, optimizes, and analyzes tables.
\fBmysqlcheck\fR
is available as of MySQL 3.23.38.
.PP
\fBmysqlcheck\fR
is similar in function to
\fBmyisamchk\fR, but works differently. The main operational difference is that
\fBmysqlcheck\fR
must be used when the
\fBmysqld\fR
server is running, whereas
\fBmyisamchk\fR
should be used when it is not. The benefit of using
\fBmysqlcheck\fR
is that you do not have to stop the server to check or repair your tables.
.PP
\fBmysqlcheck\fR
uses the SQL statements
CHECK TABLE,
REPAIR TABLE,
ANALYZE TABLE, and
OPTIMIZE TABLE
in a convenient way for the user. It determines which statements to use for the operation you want to perform, and then sends the statements to the server to be executed. For details about which storage engines each statement works with, see the descriptions for those statements in
Chapter\ 13, SQL Statement Syntax.
.PP
The
MyISAM
storage engine supports all four statements, so
\fBmysqlcheck\fR
can be used to perform all four operations on
MyISAM
tables. Other storage engines do not necessarily support all operations. In such cases, an error message is displayed. For example, if
test.t
is a
MEMORY
table, an attempt to check it produces this result:
.sp
.RS 3n
.nf
shell> \fBmysqlcheck test t\fR
test.t
note     : The storage engine for the table doesn't support check
.fi
.RE
.PP
There are three general ways to invoke
\fBmysqlcheck\fR:
.sp
.RS 3n
.nf
shell> \fBmysqlcheck [\fR\fB\fIoptions\fR\fR\fB] \fR\fB\fIdb_name\fR\fR\fB [\fR\fB\fItables\fR\fR\fB]\fR
shell> \fBmysqlcheck [\fR\fB\fIoptions\fR\fR\fB] \-\-databases \fR\fB\fIdb_name1\fR\fR\fB [\fR\fB\fIdb_name2\fR\fR\fB \fR\fB\fIdb_name3\fR\fR\fB...]\fR
shell> \fBmysqlcheck [\fR\fB\fIoptions\fR\fR\fB] \-\-all\-databases\fR
.fi
.RE
.PP
If you do not name any tables following
\fIdb_name\fR
or if you use the
\fB\-\-databases\fR
or
\fB\-\-all\-databases\fR
option, entire databases are checked.
.PP
\fBmysqlcheck\fR
has a special feature compared to other client programs. The default behavior of checking tables (\fB\-\-check\fR) can be changed by renaming the binary. If you want to have a tool that repairs tables by default, you should just make a copy of
\fBmysqlcheck\fR
named
\fBmysqlrepair\fR, or make a symbolic link to
\fBmysqlcheck\fR
named
\fBmysqlrepair\fR. If you invoke
\fBmysqlrepair\fR, it repairs tables.
.PP
The following names can be used to change
\fBmysqlcheck\fR
default behavior:
.TS
allbox tab(:);
l l
l l
l l.
T{
\fBmysqlrepair\fR
T}:T{
The default option is \fB\-\-repair\fR
T}
T{
\fBmysqlanalyze\fR
T}:T{
The default option is \fB\-\-analyze\fR
T}
T{
\fBmysqloptimize\fR
T}:T{
The default option is \fB\-\-optimize\fR
T}
.TE
.sp
.PP
\fBmysqlcheck\fR
supports the following options:
.TP 3n
\(bu
\fB\-\-help\fR,
\fB\-?\fR
.sp
Display a help message and exit.
.TP 3n
\(bu
\fB\-\-all\-databases\fR,
\fB\-A\fR
.sp
Check all tables in all databases. This is the same as using the
\fB\-\-databases\fR
option and naming all the databases on the command line.
.TP 3n
\(bu
\fB\-\-all\-in\-1\fR,
\fB\-1\fR
.sp
Instead of issuing a statement for each table, execute a single statement for each database that names all the tables from that database to be processed.
.TP 3n
\(bu
\fB\-\-analyze\fR,
\fB\-a\fR
.sp
Analyze the tables.
.TP 3n
\(bu
\fB\-\-auto\-repair\fR
.sp
If a checked table is corrupted, automatically fix it. Any necessary repairs are done after all tables have been checked.
.TP 3n
\(bu
\fB\-\-character\-sets\-dir=\fR\fB\fIpath\fR\fR
.sp
The directory where character sets are installed. See
Section\ 9.1, \(lqThe Character Set Used for Data and Sorting\(rq.
.TP 3n
\(bu
\fB\-\-check\fR,
\fB\-c\fR
.sp
Check the tables for errors. This is the default operation.
.TP 3n
\(bu
\fB\-\-check\-only\-changed\fR,
\fB\-C\fR
.sp
Check only tables that have changed since the last check or that have not been closed properly.
.TP 3n
\(bu
\fB\-\-compress\fR
.sp
Compress all information sent between the client and the server if both support compression.
.TP 3n
\(bu
\fB\-\-databases\fR,
\fB\-B\fR
.sp
Process all tables in the named databases. Normally,
\fBmysqlcheck\fR
treats the first name argument on the command line as a database name and following names as table names. With this option, it treats all name arguments as database names.
.TP 3n
\(bu
\fB\-\-debug[=\fR\fB\fIdebug_options\fR\fR\fB]\fR,
\fB\-# [\fR\fB\fIdebug_options\fR\fR\fB]\fR
.sp
Write a debugging log. A typical
\fIdebug_options\fR
string is often
\'d:t:o,\fIfile_name\fR'.
.TP 3n
\(bu
\fB\-\-default\-character\-set=\fR\fB\fIcharset_name\fR\fR
.sp
Use
\fIcharset_name\fR
as the default character set. See
Section\ 9.1, \(lqThe Character Set Used for Data and Sorting\(rq.
.TP 3n
\(bu
\fB\-\-extended\fR,
\fB\-e\fR
.sp
If you are using this option to check tables, it ensures that they are 100% consistent but takes a long time.
.sp
If you are using this option to repair tables, it runs an extended repair that may not only take a long time to execute, but may produce a lot of garbage rows also!
.TP 3n
\(bu
\fB\-\-fast\fR,
\fB\-F\fR
.sp
Check only tables that have not been closed properly.
.TP 3n
\(bu
\fB\-\-force\fR,
\fB\-f\fR
.sp
Continue even if an SQL error occurs.
.TP 3n
\(bu
\fB\-\-host=\fR\fB\fIhost_name\fR\fR,
\fB\-h \fR\fB\fIhost_name\fR\fR
.sp
Connect to the MySQL server on the given host.
.TP 3n
\(bu
\fB\-\-medium\-check\fR,
\fB\-m\fR
.sp
Do a check that is faster than an
\fB\-\-extended\fR
operation. This finds only 99.99% of all errors, which should be good enough in most cases.
.TP 3n
\(bu
\fB\-\-optimize\fR,
\fB\-o\fR
.sp
Optimize the tables.
.TP 3n
\(bu
\fB\-\-password[=\fR\fB\fIpassword\fR\fR\fB]\fR,
\fB\-p[\fR\fB\fIpassword\fR\fR\fB]\fR
.sp
The password to use when connecting to the server. If you use the short option form (\fB\-p\fR), you
\fIcannot\fR
have a space between the option and the password. If you omit the
\fIpassword\fR
value following the
\fB\-\-password\fR
or
\fB\-p\fR
option on the command line, you are prompted for one.
.sp
Specifying a password on the command line should be considered insecure. See
Section\ 7.6, \(lqKeeping Your Password Secure\(rq.
.TP 3n
\(bu
\fB\-\-port=\fR\fB\fIport_num\fR\fR,
\fB\-P \fR\fB\fIport_num\fR\fR
.sp
The TCP/IP port number to use for the connection.
.TP 3n
\(bu
\fB\-\-protocol={TCP|SOCKET|PIPE|MEMORY}\fR
.sp
The connection protocol to use. This option was added in MySQL 4.1.
.TP 3n
\(bu
\fB\-\-quick\fR,
\fB\-q\fR
.sp
If you are using this option to check tables, it prevents the check from scanning the rows to check for incorrect links. This is the fastest check method.
.sp
If you are using this option to repair tables, it tries to repair only the index tree. This is the fastest repair method.
.TP 3n
\(bu
\fB\-\-repair\fR,
\fB\-r\fR
.sp
Perform a repair that can fix almost anything except unique keys that are not unique.
.TP 3n
\(bu
\fB\-\-silent\fR,
\fB\-s\fR
.sp
Silent mode. Print only error messages.
.TP 3n
\(bu
\fB\-\-socket=\fR\fB\fIpath\fR\fR,
\fB\-S \fR\fB\fIpath\fR\fR
.sp
For connections to
localhost, the Unix socket file to use, or, on Windows, the name of the named pipe to use.
.TP 3n
\(bu
\fB\-\-ssl*\fR
.sp
Options that begin with
\fB\-\-ssl\fR
specify whether to connect to the server via SSL and indicate where to find SSL keys and certificates. See
Section\ 7.7.3, \(lqSSL Command Options\(rq.
.TP 3n
\(bu
\fB\-\-tables\fR
.sp
Overrides the
\fB\-\-databases\fR
or
\fB\-B\fR
option. All name arguments following the option are regarded as table names.
.TP 3n
\(bu
\fB\-\-use\-frm\fR
.sp
For repair operations on
MyISAM
tables, get the table structure from the
\fI.frm\fR
file so that the table can be repaired even if the
\fI.MYI\fR
header is corrupted. This option was added in MySQL 4.0.5.
.TP 3n
\(bu
\fB\-\-user=\fR\fB\fIuser_name\fR\fR,
\fB\-u \fR\fB\fIuser_name\fR\fR
.sp
The MySQL username to use when connecting to the server.
.TP 3n
\(bu
\fB\-\-verbose\fR,
\fB\-v\fR
.sp
Verbose mode. Print information about the various stages of program operation.
.TP 3n
\(bu
\fB\-\-version\fR,
\fB\-V\fR
.sp
Display version information and exit.
.SH "COPYRIGHT"
.PP
Copyright 1997\-2006 MySQL AB
.PP
This documentation is NOT distributed under a GPL license. Use of this documentation is subject to the following terms: You may create a printed copy of this documentation solely for your own personal use. Conversion to other formats is allowed as long as the actual content is not altered or edited in any way. You shall not publish or distribute this documentation in any form or on any media, except if you distribute the documentation in a manner similar to how MySQL disseminates it (that is, electronically for download on a Web site with the software) or on a CD\-ROM or similar medium, provided however that the documentation is disseminated together with the software on the same medium. Any other use, such as any dissemination of printed copies or use of this documentation, in whole or in part, in another publication, requires the prior written consent from an authorized representative of MySQL AB. MySQL AB reserves any and all rights to this documentation not expressly granted above.
.PP
Please email
<docs@mysql.com>
for more information.
.SH "SEE ALSO"
isamchk(1),
isamlog(1),
msql2mysql(1),
myisam_ftdump(1),
myisamchk(1),
myisamlog(1),
myisampack(1),
mysql(1),
mysql.server(1),
mysql_config(1),
mysql_explain_log(1),
mysql_fix_privilege_tables(1),
mysql_zap(1),
mysqlaccess(1),
mysqladmin(1),
mysqlbinlog(1),
mysqld(1),
mysqld(8),
mysqld_multi(1),
mysqld_safe(1),
mysqldump(1),
mysqlhotcopy(1),
mysqlimport(1),
mysqlshow(1),
pack_isam(1),
perror(1),
replace(1),
safe_mysqld(1)
.P
For more information, please refer to the MySQL Reference Manual,
which may already be installed locally and which is also available
online at http://dev.mysql.com/doc/.
.SH AUTHOR
MySQL AB (http://www.mysql.com/).
This software comes with no warranty.
